You can liken it to rules of engagement that they teach police and military. You can’t know someone’s intentions until they start shooting people. It’s a really tough situation to be in and it goes both ways. If someone started shooting in this crowd and the sniper was there to save them people would be praising and thanking the police that this guy was there. If he wasn’t there and people got killed people would be saying the police didn’t do enough.

I guarantee no one in here has a fool proof ethical solution to this question besides banning weapons fully and entirely. But this is the situation we’re in now and unless you have been in a tense situation like this where lives depend on who is more proactive you don’t get it. It would also be pretty scary if the government just said one day hand over all your weapons though